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排序方式: 共有134条查询结果,搜索用时 15 毫秒
1.
瑞香狼毒防治仓储害虫活性物质的研究 总被引:3,自引:0,他引:3
瑞香狼毒 (StellerachamejasmeL .)又名断肠草 ,为瑞香科狼毒属植物。瑞香狼毒在我国大部分地区均有分布 ,盛产于四川、河北、山西等地。其性苦、平、辛、有毒 ,有逐水、祛痰、破积、杀虫之功效。据文献报道 ,瑞香狼毒除了可作为中药外 ,还可以用来防治菜青虫、蚜虫、松毛虫 ,甚至可以用来杀蚊、驱蝇、灭蛆等。作者前期工作曾以瑞香狼毒根为材料 ,初步研究了根及根粉粗提物对米象、玉米象、谷蠹的防治效果。发现瑞香狼毒对米象、玉米象、谷蠹等仓储害虫均有较好的防治功效[1] 。本文以米象为试虫 ,以生物活性跟踪法对瑞… 相似文献
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4.
(R)-4-Menthenone in the synthesis of optically pure sex pheromone of the peach leafminer moth (Lyonetia clerkella) 总被引:1,自引:0,他引:1
Kharisov R. Ya. Latypova E. R. Talipov R. F. Muslukhov R. R. Ishmuratov G. Yu. Tolstikov G. A. 《Russian Chemical Bulletin》2003,52(10):2267-2269
The synthesis of (14S)-methyloctadec-1-ene, sex pheromone of the peach leafminer moth (Lyonetia clerkella), is described to demonstrate a new potential of the synthetic use of (R)-4-menthenone. 相似文献
5.
Simmonds等报道异戊烯基化的查耳酮和黄烷酮对昆虫具有拒食活性[1],Echeverri等发现,从植物Passiflorafoetida树脂中分离到的4,7-二甲氧基莰非醇(1)在很低的浓度下(40μg/g)对昆虫Dionejuno的幼虫也具有... 相似文献
6.
G. Yu. Ishmuratov M. P. Yakovleva V. A. Ganieva D. V. Amirkhanov G. A. Tolstikov 《Chemistry of Natural Compounds》2005,41(6):719-721
A synthesis of optically active 4S-methylhexanal, 1-bromo-3S-methylheptane, and 1-bromo-3S-methylundecane, which are key synthons
for several methyl-branched insect pheromones, that is based on chemically selective transformations of 6-tosyloxy- and 6-iodoisopropyl-4R-methylhexanoates
that are available from L-(-)-menthol was proposed.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 592–593, November–December, 2005. 相似文献
7.
Zhou YanXia Tan HongWei Yang ZuoYin Jia ZongChao Liu RuoZhuang Chen GuangJu 《中国科学B辑(英文版)》2007,50(2):266-271
The insect spruce budworm(Choristoneura fumiferana) produces antifreeze protein(AFP) to assist in the protection of the over-wintering larval stage and contains multiple isoforms. Structures for two isoforms,known as CfAFP-501 and CfAFP-337,show that both possess similar left-handed β-helical structure,although thermal hysteresis activity of the longer isoform CfAFP-501 is three times that of CfAFP-337. The markedly enhanced activity of CfAFP-501 is not proportional to,and cannot be simply accounted for,by the increased ice-binding site resulting from the two extra coils in CfAFP-501. In or-der to investigate the molecular basis for the activity difference and gain better understanding of AFPs in general,we have employed several different computational methods to systematically study the structural properties and ice interactions of the AFPs and their deletion models. In the context of intact AFPs,a majority of the coils in CfAFP-501 has better ice interaction and causes stronger ice lattice disruption than CfAFP-337,strongly suggesting a cooperative or synergistic effect among β-helical coils. The synergistic effect would play a critical role and make significant contributions to the anti-freeze activity β-helical antifreeze proteins. This is the first time that synergistic effect and its implica-tion for antifreeze activity are reported for β-helical antifreeze proteins. 相似文献
8.
Optimal design and operation of bioreactors for insect cell culture is facilitated by functional relations providing quantitative
information on cellular metabolite consumption kinetics, as well as on the specific cell growth rates (μG). Initial specific consumption rates of glucose, malate, and oxygen, and associated changes in μG, were measured forSpodoptera frugiperda clone 9 (Sf9) cells grown in batch suspension culture in medium containing 7–35 mM glucose, 0–16 mM malate, and 4–16 mM glutamine.
The initial specific glucose consumption rate (q
G
) could be described by a modified Michaelis-Menten equation treating malate as a “competitive” inhibitorK
1 = 6.5 mM) and glutamine as a “noncompetitive” inhibitorK
I
= 14 mM) ofq
G
, with aK
m
of 7.1 mM for glucose. All three carbon sources were found to increase μG in a saturable manner, and a modified Monod equation was employed to describe this relationship (μGmax = 0.047 h-1). The initial specific oxygen consumption rate (qO2) in Sf9 cells could be related to μG by the maintenance energy model, and it was calculated that, under typical culture conditions, about 15–20% of the cellular
energy demand comes from functions not related to growth. Fitted parameters in mathematical expression for μg: K4, Monod constant for glucose (mM); K5, modified Monod constant for malate (mM); K6, Monod constant for glutamine (mM); mo2, specific consumption rate of oxygen by the cells under zero-growth conditions (nmol/cell/h); qF, initial specific fumarate production rate (nmol/cell/ h);q
G
, initial specific glucose consumption rate (nmol/cell/h); qGmax, maximum initial specific glucose consumption rate (nmol/cell/h);q
M
, initial specific malate consumption rate (nmol/cell/h); qo2, initial specific oxygen consumption rate (nmol/cell/h); Yo2, cell yield on oxygen (cells/nmol); μ, initial specific cell growth rate (h-1); μg, initial specific cell growth rate (h-1); μGmax, maximum initial specific cell growth rate (h-1). 相似文献
9.
《Analytical letters》2012,45(11):909-922
Abstract An isotachophoretic histamine assay has been developed to determine the histamine content in hymenoptera stinging insect venoms. The amount of histamine was lowest in bee venom (0.9%) while the histamine content of vespid venom extracts varied between 2.7–5.2%. Histamine, determined quantitatively by isotachophoresis, correlated well with the histamine values achieved with reversed-phase high performance liquid chromatography. 相似文献
10.
David Terrey Jack James Ivan Tankovski Monika Dalim Michel van Spankeren Arpita Chakraborty Eric Schmitt Aman Paul 《Molecules (Basel, Switzerland)》2021,26(6)
Marine feed ingredients derived from cephalopods (e.g., squid) and crustaceans (e.g., krill) are commercially used to improve the palatability of shrimp diets. Increase in global demand for shrimps has resulted in overfishing of these marine organisms and is a matter of concern. Insect protein hydrolysate could be a sustainable alternative for the possible replacement of these marine feed ingredients. During this study, four formulations: diet A (control: not containing any palatability enhancer), diet B (containing squid meal and krill oil), diet C (containing 1% insect protein hydrolysate), and diet D (containing 2% insect protein hydrolysate) were tested for (1) time required by first subject to begin feeding (time to strike) and (2) palatability in Litopenaeus vannamei. Additionally, the chemical composition of all four diet formulations was also analyzed. Results indicate that all diets had similar crude composition. The major essential amino acids in all diets were leucine and lysine, whereas eicosapentaenoic acid was the major omega-3 fatty acid in all diets. There were no significant differences between the mean time to strike for all the tested formulations. Palatability of tested formulations was found in the following order: diet D > diet C > diet B = diet A (p < 0.05), indicating that addition of squid meal and krill oil has no effect on palatability in comparison to control, whereas inclusion of insect protein hydrolysates significantly improves the palatability of formulations. Palatability enhancement potential of insect protein hydrolysate could be attributed to the high free amino acid content and water solubility in comparison to squid meal. 相似文献